U.S. patent application number 14/855469 was filed with the patent office on 2017-03-16 for field-testable alarm module, assemblies, and testing methods thereof.
The applicant listed for this patent is Siemens Aktiengesellschaft. Invention is credited to Stephen Scott Thomas.
Application Number | 20170076577 14/855469 |
Document ID | / |
Family ID | 58257584 |
Filed Date | 2017-03-16 |
United States Patent
Application |
20170076577 |
Kind Code |
A1 |
Thomas; Stephen Scott |
March 16, 2017 |
FIELD-TESTABLE ALARM MODULE, ASSEMBLIES, AND TESTING METHODS
THEREOF
Abstract
A short circuit indicating alarm module (SCIAM). The SCIAM
includes a housing, a latch pivotally mounted relative the housing,
the latch including a latching member configured to be contacted by
a catch of a trip bar, and a plunger translatable relative to the
housing and configured, upon depressing, to contact and trip the
trip bar. Modular assemblies of a circuit breaker, trip indicating
assemblies, and methods of testing short circuit indicating alarm
modules are provided, as are other aspects.
Inventors: |
Thomas; Stephen Scott;
(Atlanta, GA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Siemens Aktiengesellschaft |
Munchen |
|
DE |
|
|
Family ID: |
58257584 |
Appl. No.: |
14/855469 |
Filed: |
September 16, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01H 71/04 20130101;
H01H 9/16 20130101 |
International
Class: |
G08B 21/18 20060101
G08B021/18; G08B 29/12 20060101 G08B029/12 |
Claims
1. A short circuit indicating alarm module, comprising: a housing;
a latch pivotally mounted relative the housing, the latch including
a latching member configured to be contacted by a catch of a trip
bar; and a plunger translatable relative to the housing and
configured, upon depressing, to contact and trip the trip bar.
2. The short circuit indicating alarm module of claim 1, wherein
the housing includes a first part and a second part, and journals
configured to receive bearing pins of the latch.
3. The short circuit indicating alarm module of claim 1, wherein
the plunger includes a plunger body including a shaft extending
from the plunger body.
4. The short circuit indicating alarm module of claim 3, wherein
the plunger body includes one or more stops that are received
against a top surface of the housing to limit extension of the
plunger.
5. The short circuit indicating alarm module of claim 3, comprising
a plunger spring biasing the plunger to a top inside surface of the
housing.
6. The short circuit indicating alarm module of claim 3, comprising
a shaft of the plunger extending out of a bottom surface of the
housing.
7. The short circuit indicating alarm module of claim 3, wherein
the plunger comprises an upper end provided in a view window of the
housing.
8. The short circuit indicating alarm module of claim 1, comprising
a slider member configured to translate upon tripping, the slider
member including a trip indicating flag.
9. The short circuit indicating alarm module of claim 8, wherein
the slider member is spring biased to an extended condition when
released to move the trip indicating flag into a view window.
10. The short circuit indicating alarm module of claim 8, wherein
the slider member includes a release member engageable with a
trigger member of the latch.
11. The short circuit indicating alarm module of claim 1, wherein
the latch includes a latch body, the latching member extending in a
first direction from the latch body, and a trigger member moveable
responsive to movement of the latching member.
12. A trip indicator assembly, comprising: a trip bar including a
catch and a trip contact surface; and a short circuit indicating
alarm module, including: a housing, a latch pivotally mounted
relative the housing, the latch including a latching member
configured to be contacted by the catch of the trip bar, and a
plunger translatable relative to the housing and configured, upon
depressing, to contact the trip contact surface of the trip
bar.
13. The trip indicator assembly of claim 12, wherein the plunger
includes a plunger body including a shaft extending from the
plunger body.
14. The trip indicator assembly of claim 12, wherein the trip
contact surface is inclined at an inclined angle of between about
25 degrees and about 50 degrees from an axial axis of the
plunger.
15. The trip indicator assembly of claim 12, comprising a shaft of
the plunger extending out of a bottom surface of the housing.
16. The trip indicator assembly of claim 12, wherein the plunger
includes a plunger body including one or more stops that are
received against a top inside surface of the housing to limit
extension of the plunger.
17. The trip indicator assembly of claim 12, comprising a plunger
spring biasing the plunger to a top inside surface of the
housing.
18. The trip indicator assembly of claim 12, wherein the plunger
comprises an upper end provided in a view window of the
housing.
19. A modular assembly of a circuit breaker, comprising: a base
housing including an accessory pocket; a trip bar mounted for
rotation in the base housing about a pivot axis, the trip bar
including a first contact area configured to be contacted by a
mechanism of the circuit breaker, a catch offset from the pivot
axis, and a trip contact surface; and a short circuit indicating
alarm module received in the accessory pocket, comprising: a
housing, a latch pivotally mounted relative the housing, the latch
including a latching member configured to be contacted by the catch
of the trip bar, and a plunger moveable relative to the housing and
configured, upon depressing, to contact the trip contact surface to
trip the trip bar as a test.
20. A method of testing a short circuit indicating alarm module of
a circuit breaker, comprising: providing a trip bar including a
catch and a trip contact surface; providing the short circuit
indicating alarm module including: a housing, a latch pivotally
mounted relative the housing, the latch including a latching member
configured to be contacted by the catch of the trip bar, and a
plunger moveable relative to the housing; and depressing the
plunger and contacting the trip contact surface of the trip bar to
trip the trip bar as a test.
Description
FIELD
[0001] The present invention relates generally to accessories for
circuit breakers, such as short circuit indicating alarm
modules.
BACKGROUND
[0002] In general, a circuit breaker operates to engage and
disengage a selected branch electrical circuit from an electrical
power supply. The circuit breaker provides current interruption
thereby providing protection to the electrical circuit from
continuous over-current conditions and/or high-current transients
due, for example. Such circuit breakers operate by separating
internal electrical contacts contained within a housing of the
circuit breaker.
[0003] In some embodiments, the circuit breakers include a
thermal-magnetic trip unit wherein the contact arms blow apart from
the stationary contacts due to magnetic forces or as a result of
thermal heating of a bimetal element. In such thermal-magnetic
circuit breakers, an accessory pocket may be provided that includes
a magnetic trip bar that rotates in response to a short circuit
that trips the circuit breaker and disconnects the electrical
contacts. Certain thermal-magnetic circuit breakers may include a
short circuit indicating accessory module in the accessory pocket.
Furthermore, certain thermal-magnetic circuit breakers may include
an internal trip switch that is activated by rotation of the trip
bar to send an electrical signal to a location indicating the
circuit breaker has been tripped. The short circuit indicating
accessory module may mechanically and visually indicate that a
short circuit trip has occurred by either sounding an alarm or
providing a visual indicator.
[0004] However, such thermal-magnetic circuit breakers including
short circuit indicating accessory modules may be deficient in some
respects. Thus, improved short circuit indicating accessory module
and assemblies including them are desired.
SUMMARY
[0005] According to a first aspect, a short circuit indicating
alarm module is provided. The short circuit indicating alarm module
includes a housing, a latch pivotally mounted relative the housing,
the latch including a latching member configured to be contacted by
a catch of a trip bar, and a plunger translatable relative to the
housing and configured, upon depressing, to contact and trip the
trip bar.
[0006] In accordance with another aspect, a trip indicator assembly
is provided. The trip indicator assembly includes a trip bar
including a catch and a trip contact surface, and a short circuit
indicating alarm module, including a housing, a latch pivotally
mounted relative the housing, the latch including a latching member
configured to be contacted by the catch of the trip bar, and a
plunger translatable relative to the housing and configured, upon
depressing, to contact the trip contact surface of the trip
bar.
[0007] In accordance with another aspect, a modular assembly of a
circuit breaker including a short circuit indicating accessory
module is provided. The modular assembly includes a base housing
including an accessory pocket, a trip bar mounted for rotation in
the base housing about a pivot axis, the trip bar including a first
contact area configured to be contacted by a mechanism of the
circuit breaker, a catch offset from the pivot axis, and a trip
contact surface, and a short circuit indicating alarm module
received in the accessory pocket, comprising a housing, a latch
pivotally mounted relative the housing, the latch including a
latching member configured to be contacted by the catch of the trip
bar, and a plunger moveable relative to the housing and configured,
upon depressing, to contact the trip contact surface to trip the
trip bar as a test.
[0008] In accordance with another aspect, a method of testing a
short circuit indicating alarm module of a circuit breaker is
provided. The method includes providing a trip bar including a
catch and a trip contact surface, providing the short circuit
indicating alarm module including a housing, a latch pivotally
mounted relative the housing, the latch including a latching member
configured to be contacted by the catch of the trip bar, and a
plunger moveable relative to the housing, and depressing the
plunger and contacting the trip contact surface of the trip bar to
trip the trip bar as a test.
[0009] Still other aspects, features, and advantages of the present
invention may be readily apparent from the following description by
illustrating a number of example embodiments, including the best
mode contemplated for carrying out the present invention. The
present invention may also be capable of different embodiments, and
its details may be modified in various respects, all without
departing from the scope of the present invention. Accordingly, the
drawings and descriptions are to be regarded as illustrative in
nature, and not as restrictive. The invention is to cover all
modifications, equivalents, and alternatives falling within the
scope of the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0010] The drawings, described below, are for illustrative purposes
only and are not necessarily drawn to scale. Like reference
numerals used in the drawings identify similar or identical
elements throughout the several views. The drawings are not
intended to limit the scope of the invention in any way.
[0011] FIG. 1A illustrates a side plan view of a trip indicator
assembly including a short circuit indicating alarm module with the
right side case removed for illustration purposes, wherein the
short circuit indicating alarm module is shown in a non-tripped
condition according to one or more embodiments.
[0012] FIG. 1B illustrates a side plan view of a trip indicator
assembly including a short circuit indicating alarm module with the
right side case removed for illustration purposes, wherein the
short circuit indicating alarm module is shown in a tripped
condition, according to one or more embodiments.
[0013] FIG. 1C illustrates an isometric view of a modular assembly
including a short circuit indicating alarm module with the right
side case removed for illustration purposes, and shown in a
non-tripped condition, according to one or more embodiments.
[0014] FIG. 1D illustrates an isometric view of a modular assembly
including a short circuit indicating alarm module with the right
side casing removed for illustration purposes, and shown in a
tripped condition, according to one or more embodiments.
[0015] FIGS. 1E and 1F illustrate isometric views of an internal
support of a base housing according to one or more embodiments.
[0016] FIG. 2 illustrates an isometric view of a latch of the short
circuit indicating alarm module according to one or more
embodiments.
[0017] FIG. 3 illustrates an isometric view of a slider member of a
short circuit indicating alarm module according to one or more
embodiments.
[0018] FIG. 4 illustrates an isometric view of a plunger of a short
circuit indicating alarm module according to one or more
embodiments.
[0019] FIG. 5A illustrates an isometric view of a left side case of
a housing of a short circuit indicating alarm module according to
one or more embodiments.
[0020] FIG. 5B illustrates an isometric view of a right side case
of a housing of a short circuit indicating alarm module according
to one or more embodiments.
[0021] FIGS. 6A and 6B illustrate first and second side isometric
views of a trip bar according to one or more embodiments.
[0022] FIG. 7A illustrates a top isometric view of a
thermal-magnetic circuit breaker including a short circuit
indicating alarm module according to one or more embodiments.
[0023] FIGS. 7B and 7C illustrate partial top isometric views of
interactive components (e.g., plunger and trip indicator flag) of a
short circuit indicating alarm module according to one or more
embodiments.
[0024] FIG. 8 illustrates a flowchart of a method of operating a
short circuit indicating alarm module according to one or more
embodiments.
DESCRIPTION
[0025] Reference will now be made in detail to the example
embodiments of this disclosure, which are illustrated in the
accompanying drawings.
[0026] In order to ensure that an accessory module is fully
functional, embodiments of the invention provide test functionality
to the accessory module, so that the operability of the accessory
module and possibly other components may be tested without having
to apply high current levels to the circuit breaker. This avoids
degradation of the electrical contacts of the circuit breaker with
which the accessory module operates. In one or more embodiments, a
short circuit indicating accessory module is provided. The short
circuit indicating accessory module, in operation, indicates that a
magnetic trip event has occurred, and a test plunger is provided,
which when depressed by an operator, engages with and moves (e.g.,
rotates) a trip bar. This allows the operator to trip the circuit
breaker to test the short circuit indicating accessory module and
also any other switching component without applying a current to
the circuit breaker. Once tripped, the short circuit indicating
accessory module provides reset capability wherein an operator can
reset the short circuit indicating accessory module upon depressing
a slider member. Once the slider member is reset, thereby releasing
the trip bar and allowing the trip bar to return to a normal
position, then the circuit breaker handle can be returned to the ON
position.
[0027] One or more embodiments of the invention are directed at a
short circuit indicating alarm module including a housing, a latch
pivotally mounted in the housing, the latch including a latching
member that is configured to be contacted by a catch of a trip bar,
and a plunger that is translatable relative to the housing and
configured, upon depressing, to contact and trip the trip bar as a
test.
[0028] In other embodiments, a trip indicating assembly for use
with a circuit breaker is provided. The trip indicating assembly
includes the short circuit indicating alarm module and a trip
bar.
[0029] One or more embodiments of the invention may be used with
one-pole or two-pole thermal-magnetic circuit breakers. Such
thermal-magnetic circuit breakers may include ratings of between
about 100 Amp to 2000 Amp (including ratings of 100 Amp, 250A Amp,
600 Amp, 1000 Amp, 1200 Amp, and 2000 Amp), for example.
[0030] These and other embodiments of short circuit indicating
alarm module, trip indicator assemblies for circuit breakers,
modular assemblies for circuit breakers including short circuit
indicating alarm module, as well as methods of testing a short
circuit indicating alarm module are described below with reference
to FIGS. 1A-8 herein.
[0031] Referring now to FIGS. 1A-1D, a trip indicating assembly 100
including a short circuit indicating alarm module 102 is provided
in accordance with one or more embodiments of the invention. Trip
indicating assembly 100 includes the short circuit indicating alarm
module 102 and a trip bar 104.
[0032] In more detail, the short circuit indicating alarm module
102 includes a housing 106, and a latch 108 pivotally mounted
relative the housing 106. Further, the latch 108 includes a
latching member 110 configured to be contacted by a catch 112 of
the trip bar 104 as the trip bar 104 rotates.
[0033] Additionally, the short circuit indicating alarm module 102
includes a plunger 114 that is translatable and reciprocatable
relative to the housing 106 and configured, upon an operator
depressing the upper end 116 thereof, to contact and manually trip
the trip bar 104 and thereby trip the circuit breaker. Short
circuit indicating alarm module 102 may further include a slider
member 107 to be described fully below.
[0034] Trip indicating assembly 100 includes the trip bar 104 with
the catch 112 as previously discussed, and further includes a trip
contact surface 124, which is configured to be engageable by an
engaging end 115 of the plunger 114. Trip contact surface 124 may
be arranged along a side of the catch 112, and may be an inclined
surface. The trip contact surface 124 may be inclined. For example,
trip contact surface 124 may be inclined at an incline angle 127 of
between about 25 degrees and about 50 degrees, as measured between
an inclined plane of the trip contact surface 124 and an axial axis
117 of the plunger 114. The plunger 114 is translatable relative to
the housing 106 along the axial axis and is configured, upon being
depressing by an operator (e.g., by depressing with a user's finger
119), to contact the trip contact surface 124 of the trip bar 104.
This causes the trip bar 104 to rotate about trip bar axle 121, as
shown in FIG. 1B. As a result, the circuit breaker may be tripped,
but also, a switch arm 123 may be rotated, which may activate a
trip switch 129 that may send a signal in signal line 131 that the
circuit breaker has been magnetically tripped. Trip switch 129 may
be an internal switch of the circuit breaker.
[0035] As can be seen in FIG. 1B, once the circuit breaker has been
tripped, the latching member 110 on the latch 108 engages the catch
112 of the trip bar 104 and holds the trip bar 104 in the tripped
position, as shown. The trip bar 104 may be returned to the ON
position after the operator moves the slider member 107 to rotate
and release the latch 108. This raises the latching member 110 and
allows the trip bar 104 to return to a non-tripped condition as
shown in FIG. 1A, then the circuit breaker can be reset and the
breaker handle can be returned to the ON position. The slider
member 107 may be moved by contacting the end of the trip
indicating flag 136 with a tool, such as a flat-head screwdriver,
for example.
[0036] FIGS. 1C and 1D illustrate isometric views of a modular
assembly 141 adapted to couple to a circuit breaker (e.g.,
thermal-magnetic circuit breaker 700 shown in FIG. 7A). Modular
assembly 141 includes the trip indicating assembly 100, which
includes the short circuit indicating alarm module 102 and trip bar
104 housed within a base housing 143. The base housing 143 includes
a mounting base 145 and an internal support 147 (FIGS. 1E-1F) that
may be configured to be coupled to the mounting base 145. Together,
the mounting base 145 and the internal support 147 provide support
and rotation surfaces for the trip bar 104 to rotate in, and an
accessory pocket 149 configured to receive the short circuit
indicating alarm module 102.
[0037] Also shown in FIG. 1C and 1D, is a thermal trip bar 151,
which may share a common axle with the trip bar 104. Trip bar 104
and thermal trip bar 151 are mounted in the mounting base 145 and
are secured in place by the internal support 147.
[0038] Referring now to FIG. 2, an isometric view of the latch 108
is shown. Latch 108 may include a latch body 226 and includes the
latching member 110. The latching member 110 may extend in a first
direction from the latch body 226. A trigger member 228 may extend
in a second direction from the latch body 226 and may be moveable
responsive to pivotal movement of the latch causes by contact
between the latching member 110 and the catch 112. Trigger member
228 interacts with a release member 332 of a slider member 107 (see
FIG. 3). Latch 108 may further include bearing pins 238 on a same
relative location on either side of the latch 108 (only one shown)
to provide a pivot axle 240 for the latch 108 to pivot around.
Bearing pins 238 may be received in bores 553 formed in the first
and second side cases 106A, 106B (see FIGS. 5A and 5B). Latch 108
may include a latch spring retainer 254 configured to interface
with the latch spring 155 (FIGS. 1A and 1B). Latch 108 may be
formed of a molded polymer material, such as Nylon, for example.
Other suitably rigid materials may be used.
[0039] Referring now to FIGS. 1A, 1B and 3, the slider member 107
is shown. Slider member 107 may include the release member 332,
which is configured to engage with a trigger member 228 of the
latch 108, a guide 334 configured to be received in a like-shaped
feature formed from one or more cavities 537A, 537B formed in
sidewalls in the first and second side cases 106A, 106B, and a trip
indicating flag 136. Trip indicating flag 136 provides a visual
indication that the circuit breaker (e.g., thermal-magnetic circuit
breaker 700 shown in FIG. 7) has been tripped. Slider member 107
may be made from a rigid material, such as polycarbonate or nylon.
Slider member 107 may be configured to translate upon tripping,
wherein the trip indicating flag 136 is extended into a view window
158. View window 158 may be provided by a recess 539 (See FIGS.
5A-5B) of the housing 106. Slider member 107 may be spring biased
to an extended condition when released from the latch 108 to move
the trip indicating flag 136 into the view window 158. Spring bias
may be provided by slider spring 150, which may register on slider
spring retainer 159. Slider spring 150 may be a coil spring, for
example. Other types of springs may be used.
[0040] Referring to FIG. 4, the plunger 114 may include a plunger
body 442 and the shaft 122 extending from a bottom side of the
plunger body 442, as shown. The plunger body 442 may include one or
more stops 444A, 444B that may be received against a top surface
(e.g., top inside surface 157) of the housing 106 to limit
extension of the plunger 114. This limit of extension may position
the upper end 116 of the plunger 114 at a position that is
approximately even with an upper surface of the housing 106. The
upper end 116 may be manually depressed by the operator to test the
operability of the short circuit indicating alarm module 102 and
any other accessory (e.g., a trip switch activated by the switch
arm 123). As is shown in FIGS. 1A and 1B, a plunger spring 148 may
be used to bias the plunger 114 to a top inside surface 157 of the
housing 106. Furthermore, the shaft 122 of the plunger 114 may
extend out of a bottom surface of the housing 106 to engage with
the trip contact surface 124 of the trip bar 104.
[0041] As shown in FIGS. 5A and 5B, the housing 106 may be made up
of the first and second side cases 106A, 106B. First and second
side cases 106A, 106B may be made from a suitable plastic material,
for example. The material may be a thermoset material, such as a
glass-filled polyester, or a thermoplastic material such as a Nylon
material (e.g., Nylon 6), for example. Other suitable insulating
materials may be used.
[0042] The first and second side cases 106A, 106B may be connected
together to form the housing 106. Housing 106 may include an upper
aperture 518 configured to receive the upper end 116 of the plunger
114. Housing 106 may include a lower aperture 520 configured to
receive a shaft 122 of the plunger 114. Housing 106 may include a
recess that comprises a view window 158 that receives the trip
indicating flag 136 therein. Housing 106 may include the bores 553
in the first and second side cases 106A, 106B that may be
configured to receive bearing pins 238 of the latch 108.
[0043] As shown in FIGS. 1A-1B and 6A-6B, the trip bar 104 includes
a first end including the catch 112 and the trip contact surface
124, which are offset from the pivot axis 660. A magnetic interface
portion 668 is operable with an armature and yoke assembly of the
circuit breaker 700 to cause tripping of the trip bar 104 due to
short circuits. Additional feature 665 may interface with the
thermal trip bar 151.
[0044] As shown in FIG. 7A, a thermo-magnetic, three-pole
embodiment of a circuit breaker 700 is depicted including the short
circuit indicating alarm module 102 in an accessory pocket 149
thereof. Circuit breaker 700 may be rated between 100 Amp and 2,000
Amp, for example. The accessory cover is shown removed, but would
be re-installed with a window knocked out to allow physical access
to the plunger 114 and visual access to the trip indicating flag
136. FIGS. 7B and 7C illustrate enlarged partial views of the view
window 158 of the short circuit indicating alarm module 102 shown
in an ON condition (FIG. 7B) and tripped condition (FIG. 7C).
[0045] According to another aspect, a method of testing a short
circuit indicating alarm module is provided. As shown in FIG. 8,
the method 800 includes, in 802, providing a trip bar (e.g., trip
bar 104) including a catch (e.g., catch 112) and a trip contact
surface (e.g., trip contact surface 124).
[0046] The method 800 includes, in 804, providing the short circuit
indicating alarm module (e.g., short circuit indicating alarm
module 102) including a housing (e.g., housing 106), a latch (e.g.,
latch 108) pivotally mounted relative the housing, the latch
including a latching member (e.g., latching member 110) configured
to be contacted by the catch (e.g., catch 112) of the trip bar
(e.g., trip bar 104), and a plunger (e.g., plunger 114) moveable
relative to the housing.
[0047] The method 800 includes, in 806, depressing the plunger
(e.g., plunger 114) and contacting the trip contact surface (e.g.,
trip contact surface 124) of the trip bar (e.g., trip bar 104) to
trip the trip bar as a test. Thus, the functionality of the short
circuit indicating alarm module 102 may be tested without having to
pass current through the circuit breaker (e.g., circuit breaker
600). Further, functionality of other accessories, such as a trip
switch 129, may be tested. Thus, testing time and cost may be
reduced, as well as wear on the electrical contacts of the circuit
breaker 700.
[0048] While the invention is susceptible to various modifications
and alternative forms, specific embodiments and methods thereof
have been shown by way of example in the drawings and are described
in detail herein. It should be understood, however, that it is not
intended to limit the invention to the particular apparatus,
assemblies, or methods disclosed herein, but to the contrary, the
intention is to cover all modifications, equivalents and
alternatives falling within the scope of the appended claims.
* * * * *